Rotary disc valve

ABSTRACT

A rotary disc valve is used in a fluid delivery system to control flow of fluid between multiple ports. The valve may include a valve body having multiple ports that are connected to the system. In addition, the valve may include a diverter and seal assembly that are disposed in the valve body. The diverter is configured to rotate about a rotational axis and to control fluid flow through the valve body in such a way that fluid enters the diverter in a first direction that is parallel to the rotational axis, fluid exits the diverter in a second direction that is parallel to the rotational axis, the second direction being opposite the first direction, and between entering and exiting, fluid flows over a portion of the diverter outer surface.

BACKGROUND

A rotary valve is a type of directional control valve that may be usedin a fluid delivery system to control fluid flow and distributionthrough the system. For example, rotary valves may be used to controlthe flow of coolant through a vehicle cooling system. The rotary valvemay include a valve body that defines several ports and a diverter thatis disposed in the valve body. The diverter is shaped to distribute theflow to predetermined ports for certain rotational orientations of thediverter within the valve body, and is rotated relative to the valvebody to control flow through the valve.

In some conventional rotary valves, the diverter moves against anelastomeric sealing element. However, elastomers have higher frictionfactors than some other conventional materials, which may result inhigher required torque to rotate the valve. Other conventional rotaryvalves employ low friction plastic materials. In such valves, thediverter may be cylindrical in shape. Cylindrical diverters, oftenreferred to as “plugs”, may result in higher operating torque and lessflexibility in placement and orientation of the inlet and outlet tubes.Still other rotary valves use a disc-shaped diverter. Such rotary discvalves may use ceramic materials for the sealing components. However,using a ceramic disc as a diverter limits the options regarding theshape of the diverter, and can be more expensive relative to divertersformed of other materials such as plastic.

SUMMARY

Complex fluid delivery systems may require a rotary disc valve that iscapable of controlling fluid flow between three, four, five or moreindividual ports of the valve body. For example, a multi-port rotarydisc valve may be used in a cooling system of an electric vehicle tocontrol flow of coolant fluid between a radiator, an electric drivemotor, a battery, vehicle electronics, and one or more bypass lines. Therotary disc valve may include a valve body that has ports that areirregularly spaced along a circumference of the valve body. In addition,the rotary disc valve may include a disc-type diverter that is disposedin the valve body and is rotatable relative to the valve body about arotational axis that is typically perpendicular to the plane in whichthe ports reside. The diverter is generally disc shaped, and includes anouter surface from which a shaft protrudes. The diverter outer surfaceis opposite a diverter seal surface via which the diverter forms a sealwith the valve body. The diverter has a three-dimensional shape thatallows the working fluid to pass on either side of it. Moreparticularly, the diverter is configured to control fluid flow throughthe valve body in such a way that fluid enters the diverter from theseal surface side and in a first direction that is parallel to the shaftrotational axis. Fluid exits the diverter in a second direction that isparallel to the rotational axis, the second direction being opposite thefirst direction. Between entering and exiting the diverter, fluid flowsover a portion of the diverter outer surface.

The shape of the diverter is such that the diverter provides one fluidflow path via a closed passageway that protrudes from the diverter outersurface, and provides another fluid flow path that permits fluid flowthrough openings in the diverter and is constrained only by the valvebody.

The diverter seal surface may be planar (e.g., flat or level and smooth,without raised areas, protrusions, recesses, indentations or surfacefeatures or irregularities) and may interface with a facing flat surfaceof a stationary, thin seal plate. The seal plate may be constructed froma plastic that has low friction and highly wear resistive properties.The seal plate is thin to provide flexibility that allows the wear plateto conform to any irregularities in the flat seal surface of thediverter. The seal plate is backed by a stationary elastic element. Theelastic element provides elasticity, biases the seal plate toward thediverter seal surface, and allows the thin seal to conform to the flatseal surface of the diverter. The elastic element also provides a staticseal between the seal plate and the valve housing. As used herein, theterm “static seal” refers to a seal in which the elements constitutingthe seal are stationary or fixed in place. The term “dynamic seal”refers to a seal in which the elements constituting the seal are capableof relative movement. In this rotary disc valve, a dynamic seal existsbetween the seal plate and the diverter seal surface, whereas stationaryseals exist between the seal plate and the elastic element, and betweenthe elastic element and the valve body. The rotary disc valve includes aspring that applies a sealing force to the diverter. The spring pushesthe diverter against the seal plate to ensure adequate sealing function,and to adapt to the changes in dimension caused by changes intemperature and due to wear of the diverter and seal plate.

In some aspects, a valve includes a valve body and a diverter that ishoused in the valve body. The valve body includes a sidewall, and a basethat closes one end of the sidewall, the sidewall and the basecooperating to define a chamber. The valve body includes valve ports,each valve port communicating with the chamber. The diverter is disposedin the chamber, and is configured to control fluid flow through thevalve body. The diverter includes a diverter sealing surface that facestoward the base, a diverter outer surface that is opposed to thediverter sealing surface and faces away from the base, and diverterthrough openings that extend between the diverter sealing surface andthe diverter outer surface. In addition, the diverter includes a shaftthat protrudes from the diverter outer surface in a directionperpendicular to the diverter sealing surface. The shaft is configuredto be driven to rotate about a rotational axis. The valve includes aseal assembly disposed in the chamber between the diverter sealingsurface and the base. The seal assembly includes a seal sealing surfacethat faces toward the diverter sealing surface, a seal outer surfacethat is opposed to the seal sealing surface and faces toward the base,and seal through openings that extend between the seal sealing surfaceand the seal outer surface. The seal assembly is fixed relative to thebase and prevents fluid flow between the diverter and the valve body andbetween abutting portions of the diverter sealing surface and the sealsealing surface. The diverter is configured to control fluid flowthrough the valve body in such a way that a) fluid enters the divertervia at least one diverter through opening in a first direction that isparallel to the rotational axis, and b) fluid exits the diverter via atleast one diverter through opening in a second direction that isparallel to the rotational axis, the second direction being opposite thefirst direction.

In some embodiments, the diverter is configured to control fluid flowthrough the valve body in such a way that, between entering and exiting,fluid flows over a portion of the diverter outer surface.

In some embodiments, the diverter includes a fluid passageway thatprotrudes from the diverter outer surface, and for some rotationalpositions of the diverter relative to the valve body, the fluidpassageway provides an enclosed fluid path between a first one of thevalve ports and a second one of the valve ports.

In some embodiments, the seal assembly includes a first sealing elementdisposed between the diverter and the base, the first sealing elementincluding the seal sealing surface and being a first material; and asecond sealing element disposed between the first sealing element andthe base, the second sealing element including the seal outer surfaceand being a second material, the second material having greaterelasticity than the first material.

In some embodiments, the seal assembly comprises a first sealing elementstacked with a second sealing element in a direction parallel to therotational axis.

In some embodiments, portions of the second sealing element have an ovalcross-sectional shape.

In some embodiments, each of the first sealing element and the secondsealing element include an outer annular portion, an inner annularportion, and struts that extend between the outer annular portion andthe inner annular portion. A surface of the outer annular portion of thesecond sealing element includes a groove. The outer annular portion, theinner annular portion and the struts each have an H-shapedcross-section.

In some embodiments, the seal assembly comprises a first sealing elementdisposed between the diverter and the base, the first sealing elementincluding the seal sealing surface; and a second sealing elementdisposed between the first sealing element and the base, the secondsealing element including the seal outer surface. The first sealingelement is prevented from rotating relative to the valve body viainterlocking engagement between a first surface feature disposed on aperiphery of the first sealing element and a second surface featuredisposed on an inner surface of the sidewall, and the second sealingelement is disposed in a groove provided in a diverter-facing surface ofthe base, and the second sealing element is prevented from rotatingrelative to the valve body via engagement between the seal outer surfaceand an inner surface of the groove.

In some embodiments, the seal assembly comprises a first sealing elementstacked with a second sealing element in a direction parallel to therotational axis. The first sealing element has first sealing elementthrough openings. The second sealing element has second sealing elementthrough openings. In addition, the first sealing element throughopenings have the same shape and dimension as the second sealing elementthrough openings and are axially aligned with the second sealing elementthrough openings.

In some embodiments, the first sealing element through openings and thesecond sealing element through openings have the shape of a circularsector.

In some embodiments, the seal assembly comprises a first sealing elementdisposed between the diverter and the base, and a second sealing elementdisposed between the first sealing element and the base. An axialdimension of the second sealing element is in a range of 3 to 15 timesthe axial dimension of the first sealing element. Additionally oralternatively, a radial dimension of the second sealing element is lessthan a radial dimension of the first sealing element.

In some embodiments, the valve includes a lid that closes an open end ofthe sidewall, and a spring disposed between the lid and the diverter,the spring biasing the diverter toward the base.

In some embodiments, the diverter is disposed on a first side of theseal assembly and the valve ports are disposed on a second side of theseal assembly, and the first side of the seal assembly is opposite thesecond side of the seal assembly.

In some embodiments, the seal assembly includes a first sealing elementdisposed between the diverter and the base, and a second sealing elementdisposed between the first sealing element and the base. In addition,the valve includes a first static seal formed between the first sealingelement and the second sealing element, a second static seal formedbetween the second sealing element and the base, and a dynamic sealformed between the first sealing element and the diverter. The divertersealing surface is a planar surface that confronts and directly contactsunder axial load a planar surface of the first sealing element, therebyrealizing the dynamic seal.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic of a vehicle cooling system including asingle-level, multi-port rotary disc valve.

FIG. 2 is a perspective view of the rotary disc valve.

FIG. 3 is an exploded perspective view of the rotary disc valve.

FIG. 4 is a partially exploded cross-sectional view of the rotary discvalve as seen along line 4-4 of FIG. 2 .

FIG. 5 is a cross-sectional view of the valve body as seen along line4-4 of FIG. 2 .

FIG. 6 is a top perspective view of the valve body.

FIG. 7 is a bottom perspective view of the valve body.

FIG. 8 is a cross-sectional view of the valve body as seen along line8-8 of FIG. 2 .

FIG. 9 is a top perspective view of the diverter.

FIG. 10 is a bottom perspective view of the diverter.

FIG. 11 is a cross-sectional view of the diverter as seen along line11-11 of FIG. 9 .

FIG. 12 is a top perspective view of the valve body with the elasticelement disposed in the valve chamber.

FIG. 13 is a top perspective view of the valve body with the elasticelement and seal plate disposed in the valve chamber.

FIG. 14 is an exploded view of the seal assembly.

FIG. 15 is a bottom perspective view of the seal assembly.

FIG. 16 is a cross-sectional view of the seal assembly.

FIG. 17 is an enlargement of the portion of FIG. 4 indicated in brokenlines.

FIG. 18 is an exploded view of an alternative embodiment rotary discvalve.

FIG. 19 is a cross-sectional view of the rotary disc valve of FIG. 18 .

FIG. 20 is a cross-sectional view of the rotary disc valve of FIG. 18with the lid, cap, and shaft seal omitted.

FIG. 21 is a top perspective view of the diverter of FIG. 18 .

FIG. 22 is a bottom perspective view of the diverter of FIG. 18 .

FIG. 23 is another bottom perspective view of the diverter of FIG. 18 .

FIG. 24 is an exploded view of the diverter and first seal subassemblyshown in FIG. 25 .

FIG. 25 is an assembled view of the diverter and first seal subassembly.

FIG. 26 is an exploded view of the valve body and second sealsubassembly shown in FIG. 27 .

FIG. 27 is an assembled view of the valve body and the second sealsubassembly.

FIG. 28 is an enlargement of the portion of FIG. 19 indicated in brokenlines.

FIG. 29 is a cross-sectional view of an alternative embodiment elasticelement.

FIG. 30 is a first perspective view of a retaining cap.

FIG. 31 is a second perspective view of the retaining cap of FIG. 30 .

FIG. 32 is a cross-sectional view of the retaining cap of FIG. 30 .

FIG. 33 is a perspective view of an alternative embodiment retainingcap.

FIG. 34 is a cross-sectional view of the retaining cap of FIG. 33 .

DETAILED DESCRIPTION

Referring to FIGS. 1-4 , a fluid delivery system 1 includes a multi-portrotary disc valve 18 that is capable of controlling fluid flow driven bypumps 8 between three, four, five or more individual fluid lines 10, 11,12, 13, 14 within the system 1. The rotary disc valve 18 may be used,for example, to control the distribution and flow of coolant in acooling system 1 of an electric vehicle. In this example, the rotarydisc valve 18 may control flow of coolant fluid between the rotary discvalve 18 and a radiator 2 that is part of a vehicle passenger cabinheating and cooling system 7, where coolant from the radiator 2 may alsocool a battery 3 and battery management system 4. In addition, therotary disc valve 18 may control fluid flow to heat exchangers 5, 6 thatsupport temperature control of other vehicle devices and systems, suchas an electric drive motor, vehicle electronics and/or electroniccontrol units and/or the oil supply. The rotary disc valve 18 includes avalve body 20 and a diverter 60 that is disposed in the valve body 20.The diverter 60 includes a valve shaft 64 that protrudes through a lid44 that closes an open end of the valve body 20. The valve shaft 64 isconfigured to be connected to a valve actuator (not shown). Uponactuation, the valve shaft 64 and the diverter 60 rotate relative to,the valve body 20 about a rotational axis 16, and the rotationalorientation of the diverter 60 relative to the valve body 20 is set viathe valve actuator. In addition, the rotary disc valve 18 has a sealassembly 80 that provides a fluid-tight seal between the valve body 20and the diverter 60. The valve body 20 includes multiple valve ports 33,34, 35, 36, 37, the number of valve ports being determined by thespecific application. The rotational orientation of the diverter 60relative to the valve body 20 determines one or more fluid flow pathsthrough corresponding ones of the valve ports 33, 34, 35, 36, 37,whereby the distribution of coolant fluid in the coolant system 1 iscontrolled. Details of the rotary disc valve 18, including the valvebody 20, the diverter 60 and the seal assembly 80, will now bedescribed.

Referring to FIGS. 2-8 , the valve body 20 includes a sidewall 21, and abase 26 that closes one end (referred to here as the “base end”) 22 ofthe sidewall 21. The sidewall 21 is a revolved section and has acircular profile when viewed in a direction parallel to the rotationalaxis 16. Although the sidewall 21 as illustrated in cylindrical, itcould alternatively be, for example, conical or ellipsoidal. Thesidewall 21 is joined at the base end 22 to a peripheral edge of thebase 26, and the sidewall 21 surrounds the base 26. The sidewall 21 andthe base 26 together form a generally cup-shaped structure that definesa valve chamber 29 therein.

The valve body 20 includes chamber walls 30 that segregate the valvechamber 29 into subchambers 32. One valve port 33, 34, 35, 36, 37communicates with each subchamber 32, and each subchamber 32 is isolatedfrom the other subchambers 32. The chamber walls 30 have exposed ends 31that are spaced apart from the base 26 and intersect the sidewall 21.The exposed ends 31 of the chamber walls 30 are aligned with a firstplane 40 that is perpendicular to the rotational axis 16 and intersectsthe sidewall 21 at an axial location between the sidewall open end 23and the valve ports 33, 34, 35, 36, 37. For each valve port, the exposedend 31 of the corresponding chamber wall 30 defines a subchamber axialopening 38, also referred to as the “non-valve port opening” of thecorresponding subchamber 32.

The valve body 20 includes a platform 24 that protrudes inward from aninner surface of the sidewall 21 and extends between adjacent pairs ofchamber walls 30. The platform 24 is axially located between thesidewall base end 22 and the first plane 40 so as to be closely adjacentto, and recessed relative to, the chamber wall exposed ends 31. Theplatform 24 and the chamber wall exposed ends 31 cooperate to provide awide, shallow platform channel 28 that receives and supports the sealassembly 80, as discussed further below.

The valve body 20 includes a post 25 that protrudes axially from theplatform 24 toward the sidewall open end 23. The post 25 is coaxial withthe rotational axis 16, and has a polygonal profile when viewed in adirection parallel to the rotational axis 16. In the illustratedembodiment, the post 25 has a pentagonal cross-sectional shape whenviewed in a direction parallel to the rotational axis 16. The post 25acts as an assembly aid and prevents rotation of portions of the sealassembly 80 with respect to the valve body 20. The post 25 is receivedin central openings 91, 105 of the first and second sealing elements 86,100 of the seal assembly 80, which each have a correspondingcross-sectional shape, as discussed in detail below.

The valve body 20 includes sidewall ribs 39 that protrude inward frominner surface of the sidewall 21. The sidewall ribs 39 are spaced apartalong an inner circumference of the sidewall 21. The sidewall ribs 39extend axially, beginning at the platform 24, and terminating at alocation that is spaced apart from the sidewall open end 23. Thesidewall ribs 39 are configured to engage with a portion of the sealassembly 80, as discussed further below.

In the illustrated embodiment, the valve body 20 includes five valveports 33, 34, 35, 36, 37, but is not limited to this number of valveports. In particular, the valve body 20 includes a first valve port 33,a second valve port 34, a third valve port 35, a fourth valve port 36and a fifth valve port 37. Each of the valve ports 33, 34, 35, 36, 37protrudes outward from the sidewall 21 along a radius of the rotationalaxis 16, and communicates with a corresponding subchamber 32. The valveports 33, 34, 35, 36, 37 extend within a common second plane 42 that isperpendicular to the rotational axis 16 and intersects the sidewall 21at an axial location between the first plane 40 and the sidewall baseend 22.

In the illustrated embodiment, the valve ports 33, 34, 35, 36, 37 arecylindrical tubes, and each valve port 33, 34, 35, 36, 37 forms acircular opening at the intersection with the valve body sidewall 21.Although, as illustrated, the valve ports 33, 34, 35, 36, 37 each havethe same length, cross-sectional shape and dimensions, the valve ports33, 34, 35, 36, 37 are not limited to this configuration. Moreover, thevalve ports 33, 34, 35, 36, 37 are not limited to the illustratedco-planar and radially oriented configuration. For example, in otherembodiments, one or more of the valve ports 33, 34, 35, 36, 37 may benon-co-planar with the other valve ports and/or may protrude from thebase rather than the sidewall. The valve ports 33, 34, 35, 36, 37 mayprotrude in a direction that is parallel to the rotational axis 16, in adirection that is perpendicular to the rotational axis 16 or at anyangle between perpendicular and parallel to the rotational axis 16. Thevalve ports 33, 34, 35, 36, 37 may protrude non-radially; an axis of agiven valve port is not required to intersect the rotational axis 16. Inmany applications, the configuration of the valve ports 33, 34, 35, 36,37 is determined by packaging requirements.

The valve ports 33, 34, 35, 36, 37, are provided at spaced-apartlocations about a circumference of the sidewall 21. In the illustratedembodiment, the first and third valve ports 33, 35 are disposed onopposed sides of the valve body 20, extend in parallel to a commondiameter of the valve body 20. The second valve port 34 is disposedmidway between the first and third valve ports 33, 35. The fourth andfifth valve ports 36, 37 are on the opposite side of the valve body 20relative to the second valve port 34. In other embodiments, the valveports 33, 34, 35, 36, 37 may have a different spacing than shown, asdetermined by the specific application.

The rotary disc valve 18 includes the lid 44 that closes the open end ofthe valve body 20. The lid 44 includes an integral cylindrical sleeve 46that is coaxial with the rotational axis 16 and extends from both theinner and outer surfaces of the lid 44. The sleeve 46 has a non-uniforminner diameter, and a shoulder 48 is disposed at the transition betweena larger-diameter portion 46(1) and a smaller-diameter portion 46(2).The larger diameter portion 46(1) and the shoulder 48 reside outside thelid 44, whereas the smaller diameter portion 46(2) is substantiallydisposed on the inside of the lid 44. The smaller diameter portion 46(2)has an inner diameter that is dimensioned to receive the valve shaft 64in a clearance fit, for example a running fit, whereby the smallerdiameter portion 46(2) serves as a bushing of the valve shaft 64. Thelarger diameter portion 46(1) includes an annular flange 49 thatprotrudes radially outward from an outer surface of the sleeve largediameter portion 46(1). The flange 49 may extend continuously about theentire outer circumference of the sleeve 46, and is axially offsetrelative to the shoulder 48.

A shaft seal 43 is disposed between the valve shaft 64 and the sleevelarge diameter portion 46(1). The shaft seal 43 provides a fluid sealbetween the valve shaft 64 and the sleeve 46. The shaft seal 43 isannular and may be formed of an elastomer that is compatible withautomotive coolant, such as ethylene propylene diene monomer (EPDM). Inthe illustrated embodiment, the shaft seal 43 is an O-ring having an “X”cross-sectional shape. In other embodiments, the shaft seal 43 may haveother cross-sectional shapes, such as, but not limited to, rectangular,oval or “I” shapes.

Referring to FIGS. 2-4 and 30-32 , the shaft seal 43 is retained on thevalve shaft 64 at an axial location corresponding to the sleeve largediameter portion 46(1) via a retaining cap 50. The retaining cap 50includes an end plate 56 that surrounds the valve shaft 64, a collar 51that protrudes from an inner periphery 56(1) of the end plate 56 andlatches 52 that protrude from an outer periphery 56(2) of the end plate56. The end plate 56, in use, is generally perpendicular to therotational axis 16. The end plate 56 has an inner surface 58 that facesthe lid 44, an outer surface 57 that faces away from the lid 44 and acircular profile when viewed in a direction parallel to the rotationalaxis 16. The end plate 56 has a central opening 59 that receives thevalve shaft 64 and defines the end plate inner periphery 56(1).

The collar 51 extends continuously along the end plate inner periphery56(1) and protrudes inward from the endplate inner surface 58. In use,the collar 51 resides between the sleeve 46 and the valve shaft 64 suchthat an end face 51(1) of the collar 51 faces the shoulder 48 with theshaft seal 43 disposed between the collar end face 51(1) and shoulder48.

The latches 52 are spaced apart along the end plate outer periphery56(2) and protrude inward from the endplate inner surface 58 toward thelid 44. In the illustrated embodiment, the retaining cap 50 includesthree latches 52 that are equally spaced apart along the end plate outerperiphery 56(2). Each latch 52 includes a leg portion 52(1) and a hookportion 52(2). A proximal end of the leg portion 52(1) is integral withthe end plate 56, and the leg portion 52(1) extends in parallel to therotational axis 16. An axial dimension of the leg portion 52(1) issufficient to position the distal end of the leg portion 52(1) at alocation corresponding to the flange 49 that protrudes radially outwardfrom an outer surface of the sleeve large diameter portion 46(1). Thehook portion 52(2) is disposed at the distal end of the leg portion52(1), and protrudes radially toward the valve shaft 64. The hookportion 52(2) is axially offset relative to the end face 51(1) of thecollar 51, and forms an interference or snap-fit engagement with theflange 49. By this configuration, the retaining cap 50 is retained onthe lid 44, with the shaft seal 43 trapped between the end face 51(1) ofthe collar 51 and the shoulder 48. As a result, the shaft seal 43 isretained on the valve shaft 64 via the retaining cap 50.

Referring to FIGS. 3-4 and 9-11 , the diverter 60 is disposed in thevalve chamber 29, and is rotatable relative to the valve body 20 aboutthe rotational axis 16. The diverter 60 is generally disc shaped, andincludes a diverter sealing surface 61 that faces toward the base 26,and a diverter outer surface 62 that is opposed to the diverter sealingsurface 61 and faces away from the base 26. The diverter sealing surface61 is planar (e.g., flat or level and smooth, without raised areas,protrusions, recesses, indentations or surface features orirregularities). The diverter sealing surface 61 faces and directlycontacts a corresponding flat surface 81 of the seal assembly 80, asdiscussed in detail below.

The diverter 60 includes a valve shaft 64 that protrudes from the centerof the diverter outer surface 62 in a direction perpendicular to thediverter sealing surface 61. The valve shaft 64 is configured to beconnected to an output shaft of the valve actuator, which drives thevalve shaft 64 to rotate about the rotational axis 16. For example, inthe illustrated embodiment, the outer surface of the valve shaft 64 mayinclude flats (shown), splines or other features that permit engagementwith an output structure of the valve actuator.

The diverter 60 includes diverter through openings 63 having a circularsector-shaped profile when the diverter 60 is viewed in a directionparallel to the rotational axis 16. The diverter through openings 63extend between the diverter sealing surface 61 and the diverter outersurface 62, whereby fluid enters and exits the diverter 60 in adirection that is parallel to the rotational axis 16. In the illustratedembodiment, the diverter 60 includes three diverter through openings63(1), 63(2) and 63(3) that are spaced apart from each other. The firstand second diverter through openings 63(1), 63(2) have a small arclength as compared to that of the third diverter through opening 63(3).For example, in the illustrated embodiment, the first and seconddiverter through openings 63(1), 63(2) have an arc length C1, (2 in arange of 30 degrees to 60 degrees and the third diverter through opening63(3) has an are length (3 in a range of 60 degrees to 120 degrees (FIG.10 ).

The diverter 60 includes a dome 65 that protrudes from the diverterouter surface 62 and overlies the third diverter through opening 63(3).In particular, the dome 65 encloses a portion of a periphery of thethird diverter through opening 63(3) whereby, for certain rotationalpositions of the diverter 60 relative to the valve body 20, fluidentering the third diverter through opening 63(3) from one valve bodysubchamber 32 may be redirected to an adjacent valve body subchamber 32.Thus, the dome 65 provides a “closed” first fluid passageway 66 withinthe rotary disc valve 18.

The first and second diverter through openings 63(1), 63(2) are notenclosed by a dome, and fluid entering one of the first and seconddiverter through openings 63(1), 63(2) from a respective subchamber 32is constrained by the valve body 20 and lid 44 and redirected toward theother of the first and second diverter through openings 63(1), 63(2).For example, after entering the diverter via the first diverter throughopening 63(1), and before exiting the diverter 60 via the seconddiverter through opening 63(2), fluid passes over a portion the diverterouter surface 62. In other words, for certain rotational positions ofthe diverter 60 relative to the valve body 20, fluid entering the firstdiverter through opening 63(1) from a corresponding first valve bodysubchamber 32(1) may be redirected to a second valve body subchamber32(2) via an “open” second fluid passageway 68 within the rotary discvalve 18, the second fluid passageway 68 passing over the diverter outersurface 62.

It is understood that the size and spacing of the first, second andthird diverter through openings 63(1), 63(2). 63(3), as well as theshape and size of the dome 65, are exemplary and in practice will dependon the specific application.

In the illustrated embodiment, the diverter 60 is formed of a plasticsuch as Polyoxymethylene (POM) or Polyphenylene Sulfide (PPS). Toprovide increased structural integrity, including resistance to bendingor flexion of the diverter 60, the diverter 60 may include a stiffeningsuperstructure 69. In the illustrated embodiment, the superstructure 69includes an annular outer rim 70, an annular inner rim 72 and spokes 74that extend between the outer rim 70 and the inner rim 72. The outer rim70 protrudes outward from a peripheral edge of the diverter outersurface 62, and extends about the entire circumference of the outersurface 62. In the illustrated embodiment, the outer rim 70 provides aportion of the dome 65 that encloses the third diverter through opening63(3). The inner rim 72 protrudes outward from the diverter outersurface 62 an axial distance that is slightly greater than that of theouter rim 70. The inner rim 72 closely surrounds the valve shaft 64. Anannular groove 73 is disposed between the inner rim 72 and the valveshaft 64 which is shaped and dimensioned to receive an end 54(2) of aspring 54 therein.

The spokes 74 extend between free ends 70(1), 72(1) of the outer andinner rims 70, 72, contributing to the stiffening effect of thesuperstructure 69. In the illustrated embodiment, the diverter 60 hasfour spokes 74(1), 74(2), 74(3), 74(4), including a first pair 74(1),74(2) of spokes 74 that overlie the radii that define the circularsector-shape of the first diverter through opening 63(1), and a secondpair 74(3), 74(4) of spokes 74 that overlie the radii that define thecircular sector-shape of the second diverter through opening 63(2). Inaddition, a first partition wall 75 extends between the outer and innerrims 70, 72 at a location corresponding to the first spoke 74(1), and asecond partition wall 76 extends between the outer and inner rims 70, 72at a location corresponding to the fourth spoke 74(4). The partitionwalls 75, 76 retain fluid within the second fluid passageway 68 anddirect fluid into the adjacent first or second diverter through opening63(1), 63(2). In addition, the partition walls 75, 76 form part, andenhance the stiffening effect, of the superstructure 69.

Referring to FIGS. 4 and 12-16 , the seal assembly 80 is disposed in thevalve chamber 29 between the diverter sealing surface 61 and the base 26of the valve body 20, more particularly between the diverter sealingsurface 61 and the platform 24. The seal assembly 80 includes a sealsealing surface 81 that faces toward, and directly contacts, thediverter sealing surface 61, and a seal outer surface 82 that is opposedto the seal sealing surface 81 and faces toward the base 26. Inaddition, the seal assembly 80 includes seal through openings 83 thatextend between the seal sealing surface 81 and the seal outer surface82. In certain rotational positions of the diverter 60, a subset of sealthrough openings 83 are aligned with one or more of the diverter throughopenings 63. The seal assembly 80 is fixed relative to the valve body20, and prevents fluid flow between the diverter 60 and the valve body20, and between abutting portions of the diverter sealing surface 61 andthe seal sealing surface 81.

The seal assembly 80 is an assembly of two sealing elements. The firstsealing element, referred to as the seal plate 86, is disposed betweenthe diverter 60 and the base 26. The second sealing element, referred toas the elastic element 100, is disposed between the seal plate 86 andthe base 26. The seal plate 86 is stacked with the elastic element 100in a direction parallel to the rotational axis 16.

The seal plate 86 includes a plate outer annular portion 87, a plateinner annular portion 88, and plate struts 89 that extend between theplate outer annular portion 87 and the plate inner annular portion 88,giving the seal plate 86 the appearance of a spoked wheel when viewed ina direction parallel to the rotation axis 16. The seal plate 86 hasplate through openings 90, which are defined between the plate outer andinner annular portions 87, 88 and each pair of adjacent plate struts 89.By this configuration, the plate through openings 90 are each generallycircular sector shaped. The plate struts 89 are not equidistantlyspaced, whereby the respective plate through openings 90 do not eachhave the same arc length.

The plate inner annular portion 88 has a central opening 91 having across-sectional shape and dimension corresponding to the cross-sectionalshape and dimension of the valve body post 25. In the illustratedembodiment, the central opening 91 has a pentagonal shape and receivesthe post 25 in a clearance fit, for example a location fit, whereby theseal plate 86 can be assembled with the valve body 20 in a predeterminedorientation.

The plate outer annular portion 87 has a plate peripheral surface 87(1)that faces the sidewall 21. Rectangular notches 87(2) are provided inthe plate peripheral surface 87(1). The notches 87(2) are spaced apartalong the circumference of the plate outer annular portion 87 and openfacing the sidewall 21. The notches 87(2) are shaped and dimensioned toreceive the sidewall ribs 39 in a clearance fit, for example a locationfit. The sidewall ribs 39 engage the notches 87(2), whereby the sealplate 86 is prevented from rotating relative to the valve body 20. Inthe illustrated embodiment, the plate peripheral surface 87(1) isgenerally circular, and slightly protrudes radially outward in thevicinity of the notches 87(2).

The diverter-facing surface 86(1) of the seal plate 86 and thebase-facing surface 86(2) of the seal plate 86 are planar (e.g., flat orlevel and smooth, without raised areas, protrusions, recesses,indentations or surface features or irregularities). The diverter-facingsurface 86(1) provides the seal sealing surface 81 of the seal assembly80. In particular, the diverter-facing surface 86(1) faces toward, anddirectly contacts, the diverter sealing surface 61. Since the diverter60 rotates relative to the seal plate 86 during valve use, seal plate 86is rigid, and is formed of a highly wear resistive plastic. In someembodiments, for example, the seal plate 86 is an ultra-high molecularweight polyethylene.

The seal plate 86 is a thin plate in that the axial dimension, orthickness, of the seal plate 86 is much less than the dimension of theseal plate 86 in a direction perpendicular to the axial dimension (e.g.,much less than the diameter of the seal plate 86). For example, in theillustrated embodiment, the diameter of the seal plate 86 may be in arange of 80 times the seal plate thickness to 160 times the seal platethickness.

The elastic element 100 includes an element outer annular portion 101,an element inner annular portion 102, and element struts 103 that extendbetween the element outer annular portion 101 and the element innerannular portion 102, giving the elastic element 100 the appearance of aspoked wheel when viewed in a direction parallel to the rotation axis16. The elastic element 100 has element through openings 104, which aredefined between the element outer and inner annular portions 101, 102and each pair of adjacent element struts 103. By this configuration, theelement through openings 104 are each generally circular sector shaped.The element struts 103 are not equidistantly spaced, whereby therespective element through openings 104 do not each have the same arclength. The element through openings 104 are aligned with correspondingones of the seal plate through openings 90, and each element throughopening 104 has the same shape and dimension as the seal plate throughopening 90 with which it is aligned. By this configuration, the plateand element through openings 90, 104 provide the seal through openings83 of the seal assembly 80.

The element inner annular portion 102 has a central opening 105 having across-sectional shape and dimension corresponding to the cross-sectionalshape and dimension of the valve body post 25. In the illustratedembodiment, the central opening 105 has a pentagonal shape and receivesthe post 25 in a clearance fit, for example a location fit, whereby theelastic element 100 can be assembled with the valve body 20 in apredetermined orientation.

The base-facing surface 100(1) of the elastic element 100 provides theseal outer surface 82 of the seal assembly 80, and the base-facingsurface 100(1) faces toward, and directly contacts, the platform 24.More particularly, the elastic element 100 rests in the platform channel28 which is shaped and dimensioned to receive the elastic elementbase-facing surface 100(1) and peripheral edges 100(2) in a clearancefit, for example a sliding fit. The engagement between the elasticelement peripheral edges 100(2) and surfaces of the platform channel 28serves to prevent relative rotation of the elastic element 100 relativeto the valve body 20. Thus, both the elastic element 100 and the sealplate 86 are fixed relative to the valve body 20.

The elastic element 100 has a greater elasticity than the seal plate 86.In addition, the elastic element 100 is formed of an elastic materialthat is compatible with the fluid that flows through the rotary discvalve 18 and meets the requirements for operating temperature anddurability. For example, when the rotary disc valve 18 is used tocontrol fluid in a vehicle coolant system, the elastic element 100 isformed of an elastomer that is compatible with automotive coolant, suchas ethylene propylene diene monomer (EPDM).

In addition to material selection, the softness and resilience of theelastic element 100 may be further increased and/or optimized byproviding the element outer and inner annular portions 101, 102 and theelement struts 103 with an irregular cross-sectional shape. For example,in some embodiments, the element outer and inner annular portions 101,102 and the element struts 103 may include a non-circular andnon-rectangular cross-sectional shape. In the illustrated embodiment,the base-facing surface 100(1) of the elastic element 100 includes afirst groove 100(4) that extends along each of the element outer andinner annular portions 101, 102 and the element struts 103. In addition,the lid-facing surface 100(3) of the elastic element 100 includes asecond groove 100(5) that extends along each of the element outer andinner annular portions 101, 102 and the element struts 103. As a result,the element outer annular portion 101, the element inner annular portion102, and the element struts 103 of the elastic element 100 each have anH shaped cross-section.

The elastic element 100 is thin in that the axial dimension, orthickness, of the elastic element 100 is much less than the dimension ofthe elastic element 100 in a direction perpendicular to the axialdimension (e.g., much less than the diameter of the elastic element100). For example, in the illustrated embodiment, the diameter of theelastic element 100 may be in a range of 10 times the elastic elementthickness to 20 times the elastic element thickness. However, thethickness of the elastic element 100 is greater than the thickness ofthe seal plate 86. For example, in the illustrated embodiment, thethickness of the elastic element 100 is in a range of 3 times to 15times the thickness of the seal plate 86. In addition, the diameter ofthe elastic element 100 is slightly less than a diameter of the sealplate 86, and a diameter of the diverter sealing surface 61 is the sameas the diameter of the seal sealing surface 81 (e.g. the same as thediverter-facing surface 86(1) of seal plate 86).

Referring to FIGS. 3-4 and 17 , the rotary disc valve 18 includes thespring 54 that is disposed between the lid 44 and the diverter 60. Inthe illustrated embodiment, the spring 54 is a coil spring thatsurrounds the valve shaft 64. One end 54(1) of the spring 54 abuts theend face 46(3) of the sleeve 46, and an opposed end 54(2) of the spring54 is disposed in the groove 73 between the diverter inner rim 72 andthe valve shaft 64. Within the assembly, the spring 54 is undercompression, whereby the spring 54 biases the diverter 60 toward thevalve body base 26 and provides a sealing force to the seal assembly 80.In particular, the spring 54 pushes the diverter 60 toward the valvebody base 26 with the seal assembly 80 disposed therebetween tofacilitate a fluid-tight seal within the rotary disc valve 18. Thespring 54 effects a fluid-tight seal 120 between diverter sealingsurface 61 and the diverter-facing surface 86(1) of the seal plate 86during relative motion between the diverter 60 and the seal plate 86.This seal 120 between relatively moving parts is referred to as a“dynamic seal.” In addition, the spring 54 cooperates with therelatively soft and resilient elastic element 100 to permit the sealassembly 80 to adapt to the changes in dimension caused by changes intemperature and due to wear of the diverter 60 and seal plate 86. Sincethe seal plate 86 is compressed against the elastic element 100 via thebiasing force of the spring 54, a fluid-tight first static seal 122exists between surfaces of the seal plate 86 and surfaces of the elasticelement 100 having direct contact, and a fluid-tight second static seal124 exists between surfaces of the elastic element 100 and surfaces ofthe valve body 20 having direct contact. The term “static seal” is usedherein to refer to a seal between relatively fixed parts.

In the embodiment of the rotary disc valve 18 described above, thediverter 60 is disposed on a first side of the seal assembly 80 and thevalve ports 33, 34, 35, 36, 37 are disposed on a second, opposed side ofthe seal assembly 80. In addition, the diverter 60 is configured tocontrol fluid flow through the valve body 20 in such a way that fluidenters the diverter 60 in a first direction D1 (FIG. 11 ) that isparallel to the rotational axis 16. For example, fluid may enter a valveport 33, pass through a corresponding valve subchamber 32, pass througha corresponding seal through opening 83 and enter a correspondingdiverter through opening 63. Within the diverter 60, fluid enters thediverter through opening 63 at the diverter sealing surface 61 and exitsthe diverter through opening at the diverter outer surface 62. Dependingon the diverter through opening 63 and the rotational position of thediverter 60 relative to the valve body 20, the fluid may then passthrough either the first (closed) fluid passageway 66 or the second(open) fluid passageway 68 to another diverter through opening 63. Thisdiverter fluid opening 63 directs fluid toward another seal throughopening 83 and its corresponding subchamber 32, whereby fluid exits thediverter 60 in a second direction D2 (FIG. 11 ) that is parallel to therotational axis 16, the second direction being opposite the firstdirection. By this configuration, between entering and exiting thediverter 60, fluid flows over a portion of the diverter outer surface 62via the first fluid passage 66 and/or the second fluid passage 68.

In the above described rotary disc valve 18, the diverter 60 and sealassembly 80 may be plastic components. In some operating conditions, forexample where the fluid passing through the valve includes debris suchas sand particles, it may be advantageous to form the dynamic seal usingceramic components to provide a fluid tight seal having increaseddurability. An alternative rotary disc valve 218 that includes a dynamicseal achieved using ceramic components will now be described.

Referring to FIGS. 18-28 , the rotary disc valve 218 is similar to therotary disc valve 18 described above with respect to FIGS. 1-17 , andcommon reference numbers are used to identify common elements. Forexample, the rotary disc valve 218 is a type of directional controlvalve that may be used in the fluid delivery system 1 to control fluidflow and distribution through the system 1, and includes the valve body20, lid 44 and the spring 54 as previously described. The rotary discvalve 218 of FIGS. 18-28 differs from the previous embodiment in that itincludes a ceramic dynamic seal 220. To that end, the rotary disc valve218 includes an alternative embodiment diverter 260 and an alternativeembodiment seal assembly 280, each disposed in the valve body 20. Thealternative embodiment diverter 260 and the alternative embodiment sealassembly 280 will now be described in detail.

The diverter 260 shown in FIGS. 18-25 is similar to the diverter 60described above with respect to FIGS. 9-11 in that the diverter 260 isgenerally disc shaped, and includes a diverter sealing surface 261 thatfaces toward the base 26, and a diverter outer surface 62 that isopposed to the diverter sealing surface 261 and faces away from the base26. The diverter sealing surface 261 faces a correspondingdiverter-facing surface 287 of the seal assembly 280. Unlike theprevious embodiment, although the diverter sealing surface 261 isgenerally planar, the diverter sealing surface 261 includes protrudingridges 267 that surround the diverter through openings 63(1), 63(2),63(3). In addition, the diverter sealing surface 261 includes bosses 268disposed between the diverter through openings 63(1). 63(2), 63(3). Eachboss 268 has a circular sector-shaped profile when the diverter sealingsurface 261 is viewed in a direction parallel to the rotational axis 16.The ridges 267 and bosses 268 together form a raised pattern thatmatches the profile of the facing element (e.g., the first elasticelement 300) of the seal assembly 280. The ridges 267 and the bosses 268cooperate to define a wide, shallow diverter channel 230 that receivesand supports a portion of the first elastic element 300 of the sealassembly 280, as discussed further below. By this configuration, thefirst elastic element 300 is rotationally located with respect to, andprevented from relative rotation with respect to, the diverter 260.

The diverter 260 further differs from the diverter 60 of the previousembodiment in that the diverter 260 includes a skirt 270 that dependsfrom an outer periphery of the diverter sealing surface 261.

The skirt 270 includes skirt ribs 272 that protrude inward from innersurface of the skirt 270. The skirt ribs 272 are spaced apart along aninner circumference of the skirt 270. The skirt ribs 272 extend axially,beginning at the diverter sealing surface 261, and terminating at alocation that is spaced apart from the skirt open end 271. The skirtribs 272 are configured to engage with a portion of the seal assembly280, as discussed further below. In the illustrated embodiment, theskirt 270 includes two skirt ribs 272.

The skirt 270 includes ledges 274 disposed at a distal end 270(2) of theskirt 270 and that protrude inward from the inner surface 270(1) of theskirt 270. The ledges 274 are spaced apart along an inner circumferenceof the skirt 270, and are used to retain a first seal subassembly 284 ofthe seal assembly 280 within the space defined by the skirt 270. In theillustrated embodiment, the skirt 270 includes three ledges, acircumferential dimension of each ledge 274 is small relative to thedimension of the skirt inner circumference.

Referring to FIGS. 18-20 and 24-28 , the seal assembly 280 is disposedin the valve chamber 29 between the diverter sealing surface 261 and thebase 26 of the valve body 20, more particularly between the divertersealing surface 261 and the platform 24. The seal assembly 280 differsfrom the seal assembly 80 described above with respect to FIGS. 3-4 and14-17 in that the seal assembly 280 includes a first seal subassembly284 and a second seal subassembly 314. The first seal subassembly 284 isdisposed within the diverter 260 so as to be surrounded by the skirt270, and is fixed relative to the diverter 260. The second sealsubassembly 314 is disposed within the valve chamber 29 so as to residein the platform channel 28, and is fixed relative to the valve body 20.The first and second seal subassemblies 284, 314 will now be describedin detail.

The first seal subassembly 284 is an assembly of two sealing elements.In particular, the first seal subassembly 284 includes a first sealplate 286 that is disposed between the diverter sealing surface 261 andthe second seal subassembly 314, and a first elastic element 300 that isdisposed between the diverter sealing surface 261 and the first sealplate 286. The first sealing element 300 is stacked with the first sealplate 286 in a direction parallel to the rotational axis 16.

The first seal plate 286 is a rigid cylindrical plate and includes afirst plate diverter-facing surface 287 that faces toward the divertersealing surface 261, and a first plate base-facing surface 288 thatfaces toward the base 26. The first seal plate 286 includes a firstplate peripheral surface 289 that extends between the first platediverter-facing and base-facing surfaces 287, 288. The first platediverter-facing and base-facing surfaces 287, 288 are planar (e.g., flator level and smooth, without raised areas, protrusions, recesses,indentations or surface features or irregularities). The diverter-facingsurface 287 also faces, and directly contacts, a corresponding facingsurface 300(2) of the intervening first elastic element 300, asdiscussed in detail below.

The first seal plate 286 includes first plate through openings 290having a circular sector-shaped profile when the first seal plate 286 isviewed in a direction parallel to the rotational axis 16. The firstplate through openings 290 extend between the first platediverter-facing and base-facing surfaces 287, 288. The first platethrough openings 290 are spaced apart from each other. The first andsecond first plate through openings 290(1), 290(2) have a small arclength as compared to that of the third first plate through opening290(3). For example, in the illustrated embodiment, the first and secondfirst plate through openings 290(1), 290(2) have an arc length of in arange of 30 degrees to 60 degrees and the third first plate throughopening 290(3) has an arc length in a range of 60 degrees to 120degrees. In the illustrated embodiment, the first plate through openings290(1). 290(2) and 290(3) are axially aligned with a corresponding oneof the diverter through openings 63(1), 63(2), 63(3), and having thesame shape and dimensions as that of the diverter through opening 63with which it is aligned.

The first plate peripheral surface 289 faces the sidewall 21.Rectangular notches 289(2) are provided in the first plate peripheralsurface 289. The notches 289(2) are spaced apart along the circumferenceof the first seal plate 286 and open facing the sidewall 21. The notches289(2) are shaped and dimensioned to receive a corresponding one of theskirt ribs 272 that protrude inward from inner surface of the diverterskirt 270 in a clearance fit, for example a location fit. The skirt ribs272 engage the notches 289(2), whereby the first seal plate 286 isprevented from rotating relative to the diverter 260. In the illustratedembodiment, the first peripheral surface 289 is circular when viewed ina direction parallel to the rotational axis 16, and includes two notches289(2).

The first plate base-facing surface 288 provides one of the dynamicsealing surfaces of the seal assembly 280. In particular, first platebase-facing surface 288 faces toward, and directly contacts, a facingsurface 316(1) of the second seal subassembly 314. Since the first sealplate 286 rotates in concert with the diverter 260 relative to thesecond seal subassembly 314 during valve use, the first seal plate 286is formed of a highly wear resistive material. For example, in theillustrated embodiment, the first seal plate 286 may be ceramic orstainless steel.

The first seal plate 286 is a thin plate in that the axial dimension, orthickness, of the first seal plate 286 is less than the dimension of thefirst seal plate 286 in a direction perpendicular to the axial dimension(e.g., less than the diameter of the first seal plate 86). For example,in the illustrated embodiment, the diameter of the first seal plate 286may be in a range of 10 times the first seal plate thickness to 20 timesthe first seal plate thickness. However, the first seal plate 286 isrelatively thick as compared to the seal plate 86 described above withrespect to FIGS. 3-4 and 14-17 .

The first elastic element 300 is similar to the elastic element 100described above with respect to FIGS. 3-4 and 14-17 , except for thearrangement of first element struts 303. In particular, the firstelastic element 300 includes a first element outer annular portion 301,a first element inner annular portion 302, and first element struts 303that extend between the first element outer annular portion 301 and thefirst element inner annular portion 302, giving the first elasticelement 300 the appearance of a spoked wheel when viewed in a directionparallel to the rotation axis 16. The first elastic element 300 hasfirst element through openings 304, which are defined between the firstelement outer and inner annular portions 301, 302 and each pair ofadjacent first element struts 303. By this configuration, the firstelement through openings 304 are each generally circular sector shaped.The first element struts 303 are not equidistantly spaced, whereby therespective first element through openings 304 do not each have the samearc length. Certain ones of the first element through openings 304 arealigned with corresponding first plate through openings 290, and eachfirst element through opening 304 has the same shape and dimension asthe first sealing element through opening 290 with which it is aligned.By this configuration, the first plate and first element throughopenings 290, 304 together provide first seal subassembly throughopenings 285.

Although in the illustrated embodiment the first element inner annularportion 302 has a polygonal central opening 305, in other embodimentsthe central opening 305 may be omitted.

The diverter-facing surface 300(1) of the first elastic element 300faces toward, and directly contacts, the diverter sealing surface 261.More particularly, the first elastic element 300 is partially receivedin the diverter channel 230 which is shaped and dimensioned to receivethe first elastic element diverter-facing surface 300(1) and peripheraledges 300(3) in a clearance fit, for example a sliding fit. Theengagement between the elastic element peripheral edges 300(3) andsurfaces of the diverter channel 230 serves to prevent relative rotationof the first elastic element 300 relative to the valve body 20. Thus,both the first elastic element 300 and the first seal plate 286 arefixed relative to the valve body 20.

The first elastic element 300 has a greater elasticity than the firstseal plate 286. In addition, the first elastic element 300 is formed ofan elastic material that is compatible with the fluid that flows throughthe rotary disc valve 18 and meets the requirements for operatingtemperature and durability. For example, when the rotary disc valve 218is used to control fluid in a vehicle coolant system, the first elasticelement 300 is formed of an elastomer that is compatible with automotivecoolant, such as ethylene propylene diene monomer (EPDM).

In addition to material selection, the softness and resilience of thefirst elastic element 300 may be further increased and/or optimized byproviding the first element outer and inner annular portions 301, 302and the first element struts 303 with an irregular cross-sectionalshape. For example, in some embodiments, the first element outer andinner annular portions 301, 302 and the first element struts 303 mayinclude a non-circular and non-rectangular cross-sectional shape. In theillustrated embodiment, the first element outer annular portion 301, thefirst element inner annular portion 302, and the first element struts303 of the first elastic element 300 have an H shaped cross-section.

The first elastic element 300 is thin in that the axial dimension, orthickness, of the first elastic element 300 is much less than thedimension of the first elastic element 300 in a direction perpendicularto the axial dimension (e.g., much less than the diameter of the firstelastic element 300). For example, in the illustrated embodiment, thediameter of the first elastic element 300 may be in a range of 10 timesthe elastic element thickness to 20 times the elastic element thickness.However, the thickness of the first elastic element 300 is approximatelyequal to the thickness of the first seal plate 286. In addition, thediameter of the first elastic element 300 is slightly less than adiameter of the first seal plate 286.

The second seal subassembly 314 is an assembly of two sealing elements.In particular, the second seal subassembly 314 includes a second sealplate 316 that is disposed between the first seal subassembly 284 andthe platform 24 of the valve body 20, and a second elastic element 330that is disposed between the second seal plate 316 and the platform 24.The second seal plate 316 and the second elastic element 330 are stackedin a direction parallel to the rotational axis 16.

The second seal plate 316 includes a second plate outer annular portion317, a second plate inner annular portion 318, and second plate struts319 that extend between the second plate outer annular portion 317 andthe second plate inner annular portion 318, giving the second seal plate316 the appearance of a spoked wheel when viewed in a direction parallelto the rotation axis 16. The second seal plate 316 has second platethrough openings 320, which are defined between the plate outer andinner annular portions 317, 318 and each pair of adjacent second platestruts 319. By this configuration, the second plate through openings 320are each generally circular sector shaped. The second plate struts 319are not equidistantly spaced, whereby the respective second platethrough openings 320 do not each have the same arc length.

Although the second plate inner annular portion 318 is free of a centralopening, a central opening may be included in some embodiments.

The second plate outer annular portion 317 has a second plate peripheralsurface 317(1) that faces the sidewall 21. Rectangular notches 317(2)are provided in the second plate peripheral surface 317(1). The notches317(2) are spaced apart along the circumference of the second plateouter annular portion 317 and open facing the sidewall 21. The notches317(2) are shaped and dimensioned to receive the sidewall ribs 39 in aclearance fit, for example a location fit. The sidewall ribs 39 engagethe notches 317(2), whereby the second seal plate 316 is prevented fromrotating relative to the valve body 20. In the illustrated embodiment,the plate peripheral surface 317(1) is circular, except that it slightlyprotrudes radially outward in the vicinity of the notches 317(2).

The second plate diverter-facing and base-facing surfaces 316(1), 316(2)are planar (e.g., flat or level and smooth, without raised areas,protrusions, recesses, indentations or surface features orirregularities). The diverter-facing surface 316(1) of the second sealplate 316 provides a portion of the dynamic seal 220 of the sealassembly 280. In particular, the diverter-facing surface 316(1) facestoward, and directly contacts, the base-facing surface 288 of the firstseal plate 286 of the first seal subassembly 284. Since the first sealsubassembly 284 rotates along with the diverter 260 relative to thevalve body 20 during valve use, second seal plate 316 is rigid, and isformed of a highly wear-resistive material. In some embodiments, forexample, the second seal plate 316 may be ceramic or stainless steel.

The second seal plate 316 is a thin plate in that the axial dimension,or thickness, of the second seal plate 316 is much less than thedimension of the second seal plate 316 in a direction perpendicular tothe axial dimension (e.g., much less than the diameter of the secondseal plate 316). For example, in the illustrated embodiment, thediameter of the second seal plate 316 may be in a range of 10 times thesecond seal plate thickness to 20 times the second seal plate thickness.However, the second seal plate 316 is relatively thick as compared tothe seal plate 86 described above with respect to FIGS. 3-4 and 14-17and has approximately the same thickness as that of the first seal plate286.

In the illustrated embodiment, the second elastic element 330 isidentical to the elastic element 100 illustrated in FIGS. 3-4 and 14-17.

The second elastic element 330 includes an second element outer annularportion 331, an second element inner annular portion 332, and secondelement struts 333 that extend between the second element outer annularportion 331 and the second element inner annular portion 332, giving thesecond elastic element 330 the appearance of a spoked wheel when viewedin a direction parallel to the rotation axis 16. The second elasticelement 330 has second element through openings 334, which are definedbetween the second element outer and inner annular portions 331, 332 andeach pair of adjacent second element struts 333. By this configuration,the second element through openings 334 are each generally circularsector shaped. The second element struts 333 are not equidistantlyspaced, whereby the respective second element through openings 334 donot each have the same arc length. The second element through openings334 are aligned with corresponding ones of the second plate throughopenings 320, and each second element through opening 334 has the sameshape and dimension as the second plate through opening 320 with whichit is aligned. By this configuration, the second plate and secondelement through openings 320, 334 together provide second sealsubassembly through openings 315.

In the illustrated embodiment, the second element inner annular portion332 has a central opening 335. In other embodiments, the central opening335 may be omitted.

The base-facing surface 330(2) of the second elastic element 330provides the seal outer surface 82 of the seal assembly 280, and thebase-facing surface 330(2) faces toward, and directly contacts, theplatform 24. More particularly, the second elastic element 330 rests inthe platform channel 28 which is shaped and dimensioned to receive theelastic element base-facing surface 330(2) and peripheral edges 330(3)in a clearance fit, for example a sliding fit. The engagement betweenthe elastic element peripheral edges 330(3) and surfaces of the platformchannel 28 serves to prevent relative rotation of the second elasticelement 330 relative to the valve body 20. Thus, both the second elasticelement 330 and the second seal plate 316 are fixed relative to thevalve body 20.

The second elastic element 330 has a greater elasticity than second sealplate 316. In addition, the second elastic element 330 is formed of anelastic material that is compatible with the fluid that flows throughthe rotary disc valve 218 and meets the requirements for operatingtemperature and durability. For example, when the rotary disc valve 218is used to control fluid in a vehicle coolant system, the second elasticelement 330 is formed of an elastomer that is compatible with automotivecoolant, such as such as ethylene propylene diene monomer (EPDM).

In addition to material selection, the softness and resilience of thesecond elastic element 330 may be further increased and/or optimized byproviding the element outer and inner annular portions 331, 332 and thesecond element struts 333 with an irregular cross-sectional shape. Forexample, in some embodiments, the element outer and inner annularportions 331, 332 and the second element struts 333 may include anon-circular and non-rectangular cross-sectional shape. In theillustrated embodiment, the second element outer annular portion 331,the second element inner annular portion 332, and the second elementstruts 333 of the second elastic element 330 each have an H shapedcross-section.

The second elastic element 330 is thin in that the axial dimension, orthickness, of the second elastic element 330 is much less than thedimension of the second elastic element 330 in a direction perpendicularto the axial dimension (e.g., much less than the diameter of the secondelastic element 330). For example, in the illustrated embodiment, thediameter of the second elastic element 330 may be in a range of 10 timesthe elastic element thickness to 20 times the elastic element thickness.However, the thickness of the second elastic element 330 isapproximately the same as the thickness of the second seal plate 316,and the diameter of the second elastic element 330 is the same as adiameter of the second seal plate 316.

Referring to FIG. 28 , the rotary disc valve 218 includes the spring 54that is disposed between the lid 44 and the diverter 260. Like theprevious embodiment, the spring 54 is under compression, whereby thespring 54 biases the diverter 260 toward the valve body base 26 andprovides a sealing force to the seal assembly 280. In particular, thespring 54 pushes the diverter 260 toward the valve body base 26 with theseal assembly 280 disposed therebetween to facilitate a fluid-tight sealwithin the rotary disc valve 218 that consists of several static sealsand a dynamic seal. In the illustrated embodiment, a fluid-tight firststatic seal 222 is provided between the diverter sealing surface 261 andthe diverter-facing surface 300(1) of the first elastic element 300. Afluid-tight second static seal 224 is provided between the base-facingsurface 300(2) of the first elastic element 300 and the diverter-facingsurface 287 of the first seal plate 286. A fluid-tight dynamic seal 220is provided between the base-facing surface 288 of the first seal plate286 and the diverter-facing surface 316(1) of the second seal plate 316.A fluid tight third static seal 226 is provided between the base-facingsurface 316(2) of the second seal plate 316 and the diverter-facingsurface 330(1) of the second elastic element 330. In addition, afluid-tight fourth static seal 228 is provided between the base-facingsurface 330(2) of the second elastic element 330 and the platformchannel 28.

The first seal subassembly 284 is surrounded by the diverter skirt 270,and has first seal subassembly through openings 285 that are alignedwith the diverter through openings 63. The second seal subassembly 314is disposed within the valve body 20 so as to rest on the platform 24,and has second seal subassembly through openings 315 that are alignedwith a corresponding subchamber 32 of the valve body 20. In certainrotational positions of the diverter 260 relative to the valve body 20,a subset of the first and second seal subassembly through openings 285,315 are aligned with each other.

While the first seal subassembly 284 prevents fluid flow between theseal assembly 280 and the diverter 260 and the second seal subassembly314 prevents fluid flow between the seal assembly 280 and the valve body20, the dynamic seal 220 is provided between abutting portions of thefirst and second seal subassemblies 284, 314. The dynamic seal 220prevents fluid flow between contacting surfaces of the first and secondseal subassemblies 284, 314, and retains fluid within the throughopenings of the seal assembly 280, where the through openings of theseal assembly 280 are constituted by aligned through openings 285, 315of the respective first and second subassemblies 284, 314.

In the rotary disc valve 218, the diverter 260 is disposed on a firstside of the seal assembly 280 and the valve ports 33, 34, 35, 36, 37 aredisposed on a second, opposed side of the seal assembly 280. Inaddition, the diverter 260 is configured to control fluid flow throughthe valve body 20 in such a way that fluid enters the diverter 260 in afirst direction D1 that is parallel to the rotational axis 16. Forexample, fluid may enter a valve port 33, pass through a correspondingvalve subchamber 32, pass through a corresponding seal through opening285, 315 and enter a corresponding diverter through opening 63. Withinthe diverter 260, fluid enters the diverter through opening 63 at thediverter sealing surface 261 and exits the diverter through opening 63at the diverter outer surface 62. Depending on the diverter throughopening 63 and the rotational position of the diverter 260 relative tothe valve body 20, the fluid may then pass through either the first(closed) fluid passageway 66 or the second (open) fluid passageway 68 toanother diverter through opening 63. The diverter fluid opening 63directs fluid toward another seal through opening 285, 315 and itscorresponding subchamber 32, whereby fluid exits the diverter 60 in asecond direction D2 that is parallel to the rotational axis 16, thesecond direction D2 being opposite the first direction D1. By thisconfiguration, between entering and exiting the diverter 60, fluid flowsover a portion of the diverter outer surface 62 via the first fluidpassage 66 and/or the second fluid passage 68.

In the illustrated embodiments, a lid 44 is provided that closes theopen end of the valve body 20. However, in other embodiments (notshown), the lid 44 may be omitted and the open end of the valve body 20may be closed by a housing of the valve actuator or other ancillarystructure.

The rotary disc valve 18 described in FIGS. 1-17 is exemplified by adynamic seal 120 in which the components of the dynamic seal (e.g., thediverter 60 and the seal plate 86) are plastic, whereas the rotary discvalve 218 described in FIGS. 18-28 is exemplified by a dynamic seal 220in which the components of the dynamic seal (e.g., the first and secondseal plates 286, 316) are ceramic. However, it is understood that thecomponents of the dynamic seal are not limited to the materialsdescribed. For example, in some embodiments, the components of thedynamic seal 120 of FIGS. 1-17 may be ceramic or other appropriatewear-resistant material, while the components of the dynamic seal 220 ofFIGS. 18-28 may be plastic or other appropriate wear-resistant material.

In the exemplary seal assemblies 80, 280 described above, the elasticelements 100, 300, 330 have been described as having an H-shapedcross-section. However, it is understood that other cross-sectionalshapes may be employed to optimize the material properties of theelastic element 100, 300, 330 for a given application. For example, insome embodiments, an alternative elastic element 100′ may be formed withthe surface grooves 100(4). 100(5) omitted, whereby the elastic element100′ may have an oval (shown in FIG. 29 ), circular, rectangular orother polygonal cross-sectional shape. In other embodiments, the elasticelement 100, 300, 330 may have an irregular cross-sectional shape suchas an I-shape, X-shape, etcetera.

Although the rotary disk valve 18, 218 is described herein as includingthe retaining cap 50 that retains the shaft seal 43 on the valve shaft,the rotary disc valve 18 is not limited to the retaining cap 50illustrated in FIGS. 2-4 and 30-32 . For example, in other embodiments,an alternative retaining cap 350 may be used. Referring to FIGS. 33-34 ,the alternative retaining cap 350 is similar to the retaining cap 50described above, and common reference numbers are used to refer tocommon elements. The retaining cap 350 of FIGS. 33-34 includes the endplate 56 and the collar 51. However, the retaining cap 350 of FIGS.33-34 is formed without the latches 52, and engages the lid 44 via aninterference fit between an outer surface of the collar 51 and an innersurface of the sleeve large diameter portion 46(1). In a manneridentical to the previously described retaining cap 50, the retainingcap 350 of FIGS. 33-34 is retained on the lid 44 with the shaft seal 43trapped between the end face 51(1) of the collar 51 and the shoulder 48.By this configuration, the shaft seal 43 is retained on the valve shaft64.

Although the valve body 20 is described herein as including a post 25that facilitates proper orientation of the seal assembly 80 with respectto the valve body 20, the post may be omitted in some embodiments, asshown in FIGS. 18-20 and 26-27 .

Selective illustrative embodiments of the fluid delivery systemincluding the rotary disc valve are described above in some detail. Itshould be understood that only structures considered necessary forclarifying the fluid delivery system and the rotary disc valve have beendescribed herein. Other conventional structures, and those of ancillaryand auxiliary components of the fluid delivery system and the rotarydisc valve, are assumed to be known and understood by those skilled inthe art. Moreover, while a working example of the fluid delivery systemand the rotary disc valve have been described above, the fluid deliverysystem and the rotary disc valve are not limited to the working exampledescribed above, but various design alterations may be carried outwithout departing from the fluid delivery system and/or the rotary discvalve as set forth in the claims.

I claim:
 1. A valve comprising: a valve body including a sidewall, and abase that closes one end of the sidewall, the sidewall and the basecooperating to define a chamber, and valve ports, each valve portcommunicating with the chamber; a diverter disposed in the chamber, thediverter configured to control fluid flow through the valve body, thediverter including a diverter sealing surface that faces toward thebase, a diverter outer surface that is opposed to the diverter sealingsurface and faces away from the base, diverter through openings thatextend between the diverter sealing surface and the diverter outersurface, and a shaft that protrudes from the diverter outer surface in adirection perpendicular to the diverter sealing surface, the shaftconfigured to be driven to rotate about a rotational axis; and a sealassembly disposed in the chamber between the diverter sealing surfaceand the base, the seal assembly including a seal sealing surface thatfaces toward the diverter sealing surface, a seal outer surface that isopposed to the seal sealing surface and faces toward the base, sealthrough openings that extend between the seal sealing surface and theseal outer surface, a first sealing element disposed between thediverter and the base, the first sealing element including the sealsealing surface and being a first material; and a second sealing elementdisposed between the first sealing element and the base, the secondsealing element including the seal outer surface and being a secondmaterial, the second material having greater elasticity than the firstmaterial, wherein the seal assembly is fixed relative to the base andprevents fluid flow between the diverter and the valve body and betweenabutting portions of the diverter sealing surface and the seal sealingsurface, the diverter is configured to control fluid flow through thevalve body in such a way that a) fluid enters the diverter via at leastone diverter through opening in a first direction that is parallel tothe rotational axis, and b) fluid exits the diverter via at least onediverter through opening in a second direction that is parallel to therotational axis, the second direction being opposite the firstdirection.
 2. The valve of claim 1, wherein the diverter is configuredto control fluid flow through the valve body in such a way that, betweenentering and exiting, fluid flows over a portion of the diverter outersurface.
 3. The valve of claim 1, wherein the diverter includes a fluidpassageway that protrudes from the diverter outer surface, and for somerotational positions of the diverter relative to the valve body, thefluid passageway provides an enclosed fluid path between a first one ofthe valve ports and a second one of the valve ports.
 4. The valve ofclaim 1, wherein the first sealing element is stacked with the secondsealing element in a direction parallel to the rotational axis.
 5. Thevalve of claim 4, wherein portions of the second sealing element have anoval cross-sectional shape.
 6. The valve of claim 4, wherein each of thefirst sealing element and the second sealing element include an outerannular portion, an inner annular portion, and struts that extendbetween the outer annular portion and the inner annular portion.
 7. Thevalve of claim 6, wherein a surface of the outer annular portion of thesecond sealing element includes a groove.
 8. The valve of claim 6,wherein the outer annular portion, the inner annular portion and thestruts each have an H-shaped cross-section.
 9. The valve of claim 1,wherein the first sealing element is disposed between the diverter andthe base; and the second sealing element is disposed between the firstsealing element and the base, and an axial dimension of the secondsealing element is in a range of 3 to 15 times an axial dimension of thefirst sealing element, where the term “axial” refers to a direction thatis parallel to the rotational axis.
 10. The valve of claim 1, whereinthe first sealing element is disposed between the diverter and the base;and the second sealing element is disposed between the first sealingelement and the base, and an outer radial dimension of the secondsealing element is less than an outer radial dimension of the firstsealing element.
 11. The valve of claim 1, the valve comprising: a lidthat closes an open end of the sidewall; and a spring disposed betweenthe lid and the diverter, the spring biasing the diverter toward thebase.
 12. The valve of claim 1, wherein the diverter is disposed on afirst side of the seal assembly and the valve ports are disposed on asecond side of the seal assembly, and the first side of the sealassembly is opposite the second side of the seal assembly.
 13. The valveof claim 1, wherein the first sealing element is disposed between thediverter and the base, the second sealing element is disposed betweenthe first sealing element and the base, and the valve comprises: a firststatic seal formed between the first sealing element and the secondsealing element, a second static seal formed between the second sealingelement and the base, and a dynamic seal formed between the firstsealing element and the diverter.
 14. The valve of claim 13, wherein thediverter sealing surface is a planar surface that confronts and directlycontacts under axial load a planar surface of the first sealing element,thereby realizing the dynamic seal.
 15. A valve comprising: a valve bodyincluding a sidewall, and a base that closes one end of the sidewall,the sidewall and the base cooperating to define a chamber, and valveports, each valve port communicating with the chamber; a diverterdisposed in the chamber, the diverter configured to control fluid flowthrough the valve body, the diverter including a diverter sealingsurface that faces toward the base, a diverter outer surface that isopposed to the diverter sealing surface and faces away from the base,diverter through openings that extend between the diverter sealingsurface and the diverter outer surface, and a shaft that protrudes fromthe diverter outer surface in a direction perpendicular to the divertersealing surface, the shaft configured to be driven to rotate about arotational axis; and a seal assembly disposed in the chamber between thediverter sealing surface and the base, the seal assembly comprising: aseal sealing surface that faces toward the diverter sealing surface, aseal outer surface that is opposed to the seal sealing surface and facestoward the base seal through openings that extend between the sealsealing surface and the seal outer surface, a first sealing elementdisposed between the diverter and the base, the first sealing elementincluding the seal sealing surface; and a second sealing elementdisposed between the first sealing element and the base, the secondsealing element including the seal outer surface, wherein the sealassembly is fixed relative to the base and prevents fluid flow betweenthe diverter and the valve body and between abutting portions of thediverter sealing surface and the seal sealing surface, the diverter isconfigured to control fluid flow through the valve body in such a waythat a) fluid enters the diverter via at least one diverter throughopening in a first direction that is parallel to the rotational axis,and b) fluid exits the diverter via at least one diverter throughopening in a second direction that is parallel to the rotational axis,the second direction being opposite the first direction, the firstsealing element is prevented from rotating relative to the valve bodyvia interlocking engagement between a first surface feature disposed ona periphery of the first sealing element and a second surface featuredisposed on an inner surface of the sidewall, and the second sealingelement is disposed in a groove provided in a diverter-facing surface ofthe base, and the second sealing element is prevented from rotatingrelative to the valve body via engagement between the seal outer surfaceand an inner surface of the groove.
 16. The valve of claim 15, whereinthe second sealing element includes the seal outer surface and being asecond material, the second material having greater elasticity than thefirst material.
 17. A valve comprising: a valve body including asidewall, and a base that closes one end of the sidewall, the sidewalland the base cooperating to define a chamber, and valve ports, eachvalve port communicating with the chamber; a diverter disposed in thechamber, the diverter configured to control fluid flow through the valvebody, the diverter including a diverter sealing surface that facestoward the base, a diverter outer surface that is opposed to thediverter sealing surface and faces away from the base, diverter throughopenings that extend between the diverter sealing surface and thediverter outer surface, and a shaft that protrudes from the diverterouter surface in a direction perpendicular to the diverter sealingsurface, the shaft configured to be driven to rotate about a rotationalaxis; and a seal assembly disposed in the chamber between the divertersealing surface and the base, the seal assembly including a seal sealingsurface that faces toward the diverter sealing surface, a seal outersurface that is opposed to the seal sealing surface and faces toward thebase, and seal through openings that extend between the seal sealingsurface and the seal outer surface, wherein the seal assembly is fixedrelative to the base and prevents fluid flow between the diverter andthe valve body and between abutting portions of the diverter sealingsurface and the seal sealing surface, the diverter is configured tocontrol fluid flow through the valve body in such a way that a) fluidenters the diverter via at least one diverter through opening in a firstdirection that is parallel to the rotational axis, and b) fluid exitsthe diverter via at least one diverter through opening in a seconddirection that is parallel to the rotational axis, the second directionbeing opposite the first direction, the seal assembly comprises a firstsealing element stacked with a second sealing element in a directionparallel to the rotational axis, the first sealing element has firstsealing element through openings, the second sealing element has secondsealing element through openings, and the first sealing element throughopenings have the same shape and dimension as the second sealing elementthrough openings and are axially aligned with the second sealing elementthrough openings.
 18. The valve of claim 17, wherein the first sealingelement through openings and the second sealing element through openingshave the shape of a circular sector.